The two young forwards flanked Romelu Lukaku from the start for the first time on Saturday and United ran out 4-1 winners over Newcastle United at Old Trafford, with Martial scoring for the hosts and Rashford assisting for Paul Pogba’s goal.
That win kept United in second place, still eight points behind Manchester City at the top, with both the youngsters impressing throughout.
It was only the 12th time Rashford and Martial have been on the pitch at the same time in their careers, with both playing slightly to the left of Lukaku, with Juan Mata forced to take up his position on the right.
And Mourinho revealed the reason for this was because neither player liked being on the right and it took time to get the balance right against Newcastle.
“They both like to play in the same position and that is difficult,” Mourinho said. “They both prefer to play on the left than the right, both playing with another striker through the middle, we lose a point of contact with the midfield that we are used to, with the player playing behind the striker.
“But we found then a certain balance and when they start finding, sometimes both, one opening the left and one on the mid-left between the striker and the left winger, it was the moment where we start creating more.
“But to be honest Newcastle was probably the team, not in the second-half, but in the first-half which come here and we felt a bit of instability in our defensive areas, and that was clearly not because of the defensive players but because of our balance.
“So to play them [Martial and Rashford] together gives us things but also takes some things from us.”
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